This view of the Oliver Red River Special thresher shows the large red pulley on top that runs the entire feeder housing, the apron and the bundle cutters on top. Three or four knives cut the twine wrapped around the bundles when they come in so the grain will lay flat and go into the cylinder. The large green gear in the center runs the feeder apron, chains and other mechanisms. It can be changed with two other sizes to alter the speed of the product coming into the apron, depending on how thick the grain is, how many workers are available and how wet the grain is. The pulley next to the gear at its left is the clutch, which can be set so if something catches on the apron, it will slip and not be stripped or destroyed. The half-circle gear next to it can be adjusted in response to the height of the straw pan inside. The long pulleys at left drive everything on this side of the machine.
Photo Courtesy Bill Vossler